Backpack mounted pivoting motor for concrete finishing

Abstract

A portable concrete finishing system comprising a backpack-borne, pivoting engine that powers a selected tool. A rigid frame supporting a four cycle motor is connected to the tool by a flexible power shaft. A removable vibration absorption system isolates the user from stress. A pair of integral, divergent shoulder harnesses protrude from the backpack top and an encircling, semi-elastic waist belt encircles the bottom. An integral belt tensioner permits the user to adjust belt tightness. The dampening system comprises a removable pad that has a pair of slip-on cuffs to captivate the ends of both shoulder harnesses. The frame also mounts a pair of ergonomic controls that may be easily manipulated by the user to control the power unit. A bracket assembly secures the engine to the frame. The assembly comprises a bracket pivotally coupled to a support that is attached directly to the frame. The bracket and support are hinged by a pin. The bracket directly attaches to the engine. The engine pivots in response to tool manipulation. The elongated flex-cable that connects the tool to the four cycle engine includes an internal compensator that accommodates thermal expansion and contraction.

What is claimed is: 
     
       1. A portable concrete treatment system adapted to be worn and transported by a user around a job site for consolidating plastic concrete, said system comprising: a four cycle internal combustion motor for powering the system;   backpack means for transporting said motor, said backpack means comprising protruding shoulder harness means for engaging the shoulders of said user;   means for mounting said motor to said backpack means, said mounting means comprising: a bracket supporting said motor;   a support centered upon and attached to said backpack; and,   means for pivotally coupling said bracket to said support, said coupling means establishing a pivot axis substantially parallel with the user and substantially perpendicular to the job site;     a flexible connection quick connected to and powered by said motor and adapted to be carried by said user about a job site for powering a concrete tool;   compensator means within said connection for accommodating stresses; and,   said concrete tool for finishing concrete adapted to be remotely powered by said connection while said user supports said backpack means.   
     
     
       2. The system defined in claim 1 wherein said concrete tool is a portable strike off vibrated by connection with said motor. 
     
     
       3. The system defined in claim 2 wherein said compensator means torsionally couples said flexible connection to said motor, and said compensator means is slidable within said flexible connection in response to heat buildup and axial stresses to prevent over tensioning of said connection. 
     
     
       4. The system defined in claim 3 wherein said backpack means comprises a dampening system for absorbing vibrations generated during operation and isolating the user from them. 
     
     
       5. The system defined in claim 4 wherein said concrete tool is a portable strike off vibrated by connection with said motor. 
     
     
       6. The system defined in claim 4 wherein said dampening system comprises an elongated pad selectively secured to said backpack means. 
     
     
       7. The system defined in claim 1 wherein said compensator means is axially slidable within said flexible connection in response to heat buildup or stress to prevent tensioning of said connection. 
     
     
       8. A portable, backpack mounted concrete finishing system adapted to be worn and transported by a user about a job site when finishing plastic concrete, said system comprising: an internal combustion motor for powering the system:   a backpack worn by the user to support said motor, said backpack comprising:   a rigid frame comprising shoulder harness means for substantially supporting the backpack on the user's shoulders;   belt means attached to said frame for securing the backpack to the user;   tensioning means for tightening said belt means;   control means for manipulating said motor, said control means mounted on said frame;   vibration isolator means for isolating motor vibration from the user;   dampening means mounted on said shoulder harness means for absorbing vibrations produced by said motor;   means for pivotally mounting said motor on said backpack, said mounting means comprising:   a bracket for supporting said motor;   a support centered upon and attached to said backpack; and,   means for pivotally coupling said bracket to said support, said coupling means establishing a pivot axis substantially parallel with the user and substantially perpendicular to the site;   a portable tool for finishing concrete adapted to be remotely powered by said motor while said user supports said backpack;   flexible connection means for connecting said motor to said tool;   whereby said means for pivotally mounting said motor to said backpack eliminates the transfer of torsional stain from said flexible connection means to said backpack when said tool is manipulated.   
     
     
       9. The system defined in claim 8 wherein said flexible connection means comprises an elongated flex drive having two spaced apart ends, the first of said ends coupled to said tool and the second of said ends quick connected to said motor. 
     
     
       10. The system defined in claim 8 further comprising compensator means for coupling said flexible connection means to said motor. 
     
     
       11. The system defined in claim 8 wherein said tool comprises a pendulous vibrator. 
     
     
       12. The system defined in claim 8 wherein said tool comprises a strike-off. 
     
     
       13. A portable concrete vibrating system adapted to be worn and transported by a user over a construction site for consolidating plastic concrete, said system comprising: a backpack worn by a user for supporting and transporting the system;   a motor for powering the system;   means for hingedly mounting said motor to said backpack;   a vibrator powered by said motor, said vibrator comprising an elongated casing and a pendulum shaft rotatably, generally coaxially disposed therewithin for forcibly impacting the casing in response to the movement of said pendulum shaft;   a flexible connection between said backpack and said vibrator extending between the user and the concrete; and, said flexible connection quick connected to and powered by said motor and adapted to be carried by said user about a job site for powering a concrete tool; and,   said concrete tool for finishing concrete adapted to be remotely powered by said motor while said user supports said backpack; and,   said means for hingedly mounting said motor to said backpack comprising: a bracket for supporting said motor;   a support centered upon and attached to said backpack; and,   means for pivotally coupling said bracket to said support, said coupling means establishing a pivot axis substantially parallel with the user and substantially perpendicular to the site;     compensating means within said flexible connection for accommodating axial stresses caused by said vibrator, wherein said compensating means torsionally couples said flexible connection to said motor, and said compensating means is slidable within said flexible connection in response to heat buildup and axial stresses to prevent over tensioning of said flexible connection; and,   a dampening system comprising an elongated pad selectively secured to said backpack.